The objective of this proposal is to devlop and evaluate an immunodiagnostic method for the detection of prostatic cancers. We will search for prostatic-associated (specific) antigen/enzymes from prostatic glands and blood of patients with prostatic carcinoma. The antigens (and/or enzymes) will further be purified, characterized and specific immune sera will be raised in rabbits and/or goats. Using the specific antiserum and the purified antigens (or enzymes), an immunoassay procedure will be developed for the determination of the prostatic tumor antigen (or enzyme) as a marker for the presence of early tumor and for the evaluation of treatment will be determined.